cabsf, cabs, cabsl

 

C

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Variadic function support

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Date and time utilities

Input/output support

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Concurrency support(C11)

Technical Specifications

Symbol index

 

Numerics

Common mathematical functions

Floating-point environment(C99)

Pseudo-random number generation

Complex number arithmetic(C99)

Type-generic math(C99)

Bit manipulation(C23)

Checked integer arithmetic(C23)

 

Complex number arithmetic

Types and the imaginary constant
complex (C99) _Complex_I (C99)     CMPLX (C11)	imaginary (C99) _Imaginary_I (C99) I (C99)
Manipulation
cimag (C99) creal (C99) carg (C99)	cabs (C99) conj (C99) cproj (C99)
Power and exponential functions
cexp (C99) clog (C99)	cpow (C99) csqrt (C99)
Trigonometric functions
ccos (C99) csin (C99) ctan (C99)	cacos (C99) casin (C99) catan (C99)
Hyperbolic functions
ccosh (C99) csinh (C99) ctanh (C99)	cacosh (C99) casinh (C99) catanh (C99)

 

Defined in header <complex.h>
float       cabsf(floatcomplex z );	(1)	(since C99)
double      cabs(doublecomplex z );	(2)	(since C99)
longdouble cabsl(longdoublecomplex z );	(3)	(since C99)
Defined in header <tgmath.h>
#define fabs( z )	(4)	(since C99)

1-3) Computes the complex absolute value (also known as norm, modulus, or magnitude) of z.

4) Type-generic macro: if z has type longdoublecomplex or longdoubleimaginary, cabsl is called. If z has type floatcomplex or floatimaginary, cabsf is called. If z has type doublecomplex or doubleimaginary, cabs is called. For real and integer types, the corresponding version of fabs is called.

Parameters

z

-

complex argument

Return value

If no errors occur, returns the absolute value (norm, magnitude) of z.

Errors and special cases are handled as if the function is implemented as hypot(creal(z), cimag(z))

Example

Run this code

#include <stdio.h>#include <complex.h>   int main(void){doublecomplex z =1.0+1.0*I;printf("%.1f%+.1fi cartesian is rho=%f theta=%f polar\n", creal(z), cimag(z), cabs(z), carg(z));}

Output:

1.0+1.0i cartesian is rho=1.414214 theta=0.785398 polar

References

• C11 standard (ISO/IEC 9899:2011):

• 7.3.8.1 The cabs functions (p: 195)

• 7.25 Type-generic math <tgmath.h> (p: 373-375)

• G.7 Type-generic math <tgmath.h> (p: 545)

• C99 standard (ISO/IEC 9899:1999):

• 7.3.8.1 The cabs functions (p: 177)

• 7.22 Type-generic math <tgmath.h> (p: 335-337)

• G.7 Type-generic math <tgmath.h> (p: 480)

See also

cargcargfcargl (C99)(C99)(C99)	computes the phase angle of a complex number (function)
abslabsllabs (C99)	computes absolute value of an integral value (\(\small{|x|}\)|x|) (function)
fabsfabsffabsl (C99)(C99)	computes absolute value of a floating-point value (\(\small{|x|}\)|x|) (function)
hypothypotfhypotl (C99)(C99)(C99)	computes square root of the sum of the squares of two given numbers (\(\scriptsize{\sqrt{x^2+y^2} }\)√x2 +y2 ) (function)
C++ documentation for abs